The invention relates to a motor housing and a pole cover for an electric motor drive, especially for window lift or sunroof motors in a motor vehicle, according to the type of the independent claims.
Such housings for window lift motors or other actuating drives are generally known, DE-GM 29702525.2. The housings shown there disclose essentially two parts, a pole cover made of metal and a drive housing made of metal or plastic. In these motors there is usually a plastic brush holder located between the pole cover and drive housing which also serves as a seal. An integrated plug with a cable gland on the brush holder for supplying power to the motor extends from the motor. Both housing parts are connected together such that the plug extends undisturbed between two screw connections. The housing is constructed such that the brush holder with the plug connection can be rotated by 180xc2x0 and the motor power supply can be brought in from the left or right side. There is no space however provided here in the housing for a printed circuit board.
In another version of the motor with integrated electronics EP 0 474 904 B1 and integrated electronics housing, the brush holder is located on a printed circuit board which is parallel to the motor shaft. The printed circuit board is brought out parallel to the motor shaft and laterally alongside to an electronic plug. This can however result in a collision of the printed circuit board with one of the screw connection between the pole cover and the drive housing. This problem is avoided here by giving the printed circuit board a very narrow, neck-like configuration in the area of the housing screw connection and bringing it out past the screw connection of the pole cover and drive housing. This form of printed circuit board is however quite expensive to produce and represents a severe limitation to placing on the printed circuit board larger area components. A further drawback to this solution is that different pole covers have to be manufactured for different housing types, which creates difficulties in manufacturing and is overall quite cost-intensive. By selecting a pole cover with three receptacles it would no longer be possible to exchange the plug with a motor with no electronics. This is considered however a distinct drawback. Furthermore it is necessary for different motor versions, when for example later space considerations dictate that the printed circuit board be brought out on the other side of the motor, to design completely new individual housing parts whereby the screw points between the pole cover and the drive housing are placed so that the printed circuit board can be brought out on this side.
The arrangement according to the invention having the features of the main claim has the advantage that a universal pole cover is created that can be fitted to various drive- and electronics housings for various motor housings. The resulting modular production process offers enormous advantages. The most expensive housing part, the pole cover, can be produce in very large quantities, and the associated less expensive housing parts for the drive, electronics and plug can be varied cost favorably depending on the requirements of the motor housing, without restricting the functionality of the various motor housing types. Furthermore the customary high connection strength is achieved even in the various constellations, since - as usual - four connection points can be used.
The features described in the dependent claims make possible advantageous further embodiments of the arrangement according to the main claim. If the pole cover has at least one more receptacle than the housing closing off the pole cover, and if one receptacle and/or counterreceptacle is not used, the result is a great degree of flexibility for combining the pole covers with various housing parts. By not using receptacles and/or counterreceptacles, the space one has save can be used for various specifications of the various housings.
The arrangement of the receptacles in the corners of a rectangle has the advantage of compatibility with currently available drive housings. These pole covers can also be used for actuating motors without electronics. If a fifth receptacle is provided on a short side of the rectangle, the overall width of the motor housing is not increased, which is important for installing it in motor vehicle roofs and doors. In addition, this fifth receptacle can then better absorb the forces of two adjacent, optionally unused receptacles.
In the case of a pole cover with five receptacles for a motor without electronics, the plug neck can be arranged as desired on the left or right. This is made possible by placing the four receptacles in the corners of the rectangle, which are arranged point-symmetric to the motor shaft. This represents a significant gain in flexibility for installing and wiring up the motors. By using a sixth receptacle the connection strength of the motor housing is further increased without making the motor housing wider. In this solution the form and length of the plug neck is adapted to the location of the sixth receptacle.
If the housing closing off the pole cover is a drive housing, and if a brush holder with a connecting plug is attached in between, the motor housing can be used fully interchangeably with traditional motors. The positioning of the fifth receptacle opposite the plug is advantageous, since the result is that no construction changes are necessary for the plug neck.
Furthermore the same pole cover can also be used for motors having integrated electronics without preventing any optimal arrangement of the printed circuit board. By not using one of the receptacles in the corner of the rectangle, the printed circuit board in the motor with electronics can extend parallel to the flattened drive housing wall parallel to the long side of the rectangle, without being hindered by one of the connection elements that are otherwise located in all four corners of the rectangular pole cover flange. An advantage of this method of installing the printed circuit board is the possibility of fitting larger electronic components such as relays on the printed circuit board without being restricted by the housing wall. Moreover, the mounting of the printed circuit board is simplified by its parallel orientation to the housing wall.
By screwing additional optional, asymmetrically arranged receptacles, the strength as compared with screwing having three fastening points is increased. This has the advantage that the constructional width of the motor corresponding to the short side of the named rectangle is not increased. The location of the fifth receptacle next to the unused fastening receptacle ensures that the joining strength is not diminished by the unused fastening receptacle.
The compatibility of the pole cover with the housing closing off the pole cover for motors having only one plug, for motors with provision for a plug-in electronic module and motors having integrated electronics make the production independent of any rapid market changes in the direction of integrated electronics. The still current need for purely mechanical motors is accounted for in this product by the fact that the plug for the power supply can be optionally located on the left or right.
Such a solution for the motor housing having only one type of pole cover with five or six receptacles for all motor types is of course very cost-effective and favorable to manufacturing.